Clear Gloss is usually used on metallic paint when cars are manufactured. Some manufacturers still apply non-metallic paints this is also known as the (COB) clear over base procedure. When a scratch occurs in metallic paint there are two types of scratch depths, light scratches that are confined to only the clear layer which can be resolved adequately with just rubbing / polishing compounds and clear gloss. The the other type of scratch where the gloss and the lower paint layers are scratched will need a more lengthy process requiring more procedure and products.
The greatest indicator to identify whether the scratch is confined to the clear gloss coat or not it to apply our touch up paint Clean-up solution and as it cleans and gives a wet look to the repair area making apparent if the scratch is indeed in the color or the clear. If the scratching in the paint is in the clear layer as the clean up solution passes the scratch will momentarily disappear and returning as the clean-up solution dries. You should only use the clear to fix the scratch. The parts of the scratch that did not disappear with the Clean-up will need to be repaired with additional paint repair products. Note: Gloss Clear may be used on non-metallic paint if the damage is confined to the color coat only
Always apply the factory clear only where needed, in other words do not put clear gloss on good paint, insert the product only to the effected area applying it to where the clear has been removed.